The Use of a High Energy Feed for the Improvement of Trout Farm Effluents

The aquaculture industry has experienced a great expansion in recent years. Along with this growth, increased regulatory attention has been directed towards aquacultural effluents. The problem with the majority of these discharges is the solids and nutrient spikes that occur during times of high farm activity. Several studies have proven that these discharges have the potential to adversely affect downstream water quality. Although several treatment options are currently in use, the use of Best Management Practices (BMPs)has been recommended in recent years to improve the quality of these discharges. The implementation of one of these BMPs, the use of a high energy feed, was the focus of this study. In two separate experiments at trout raising facilities, the effluents of basins receiving a high energy feed were compared to similar basins receiving a standard trout grower feed. The water quality parameters of main concern were total suspended solids, total Kjeldahl nitrogen (TKN) and total ammonia nitrogen (TAN). The results of these studies showed that the effluents of basins receiving a high energy feed generally contained significantly lower concentrations of TSS, but higher amounts of TKN than those receiving a standard grower feed.